This invention generally relates to a carburetor controlling system having an electrically-heated choke system which converts power supplied from a battery into a mechanical energy and controls an opening and closing operation of a choke valve by the mechanical energy and having a fast idle system which controls an opening and closing operation of a throttle valve, and more particularly to a carburetor controlling system further including a means provided in the fast idle system for converting an electrical energy from the battery and a control circuit provided among the battery, the electrically-heated choke system and the fast idle system for controlling power supply to both the systems in response to the detected atmospheric temperature so as to individually and properly perform the opening and closing operations of the choke valve and the throttle valve.
A conventional carburetor system for an internal combustion engine in an automobile is typically provided with an electrically-heated choke system having a heat generating member such as Nichome wire which is heated by the power supplied from a battery mounted in the automobile and a thermo-sensitive member such as a bimetal which is physically deformed by heat from the heat generating member for controlling the opening and closing operation of a choke valve by the physical deformation of the thermo-sensitive member, and with a fast idle system for controlling the opening and closing operation of a throttle valve in an idling-up operation to accelerate the warm-up of a cold engine.
Heretofore, it has been imposed to minimize fuel consumption in an automobile. A method of solving the problem of fuel consumption is proposed to open a choke valve as early as possible.
However, in a conventional carburetor controlling system, the electrically-heated choke system is designed in such a manner that electrical power is directly supplied from the battery through an ignition key switch to the choke system, and the fast idle system is connected through a power transmitting means such as a lever and a cam to the electrically-heated choke system. Accordingly, even if the structure of the electrically-heated choke valve is modified so as to open the choke valve as early as possible, it is difficult to fully attain the required characteristics of the choke valve opening degree which are different at normal temperature and at low temperature. Furthermore, the fast idle system is apt to erroneously operate at early opening operation of the choke valve. In the worst case, the throttle valve opens undesirably early thereby causing a malfunction of an engine. For the abovementioned reasons, it has been considered difficult to thoroughly solve the problem of fuel consumption.